Apparatus for inflating a vehicle occupant restraint using a mixture of gases

ABSTRACT

An apparatus for inflating a vehicle occupant restraint includes containing means for receiving gases to provide a combustible mixture of the gases. An igniter is activated to effect ignition of the mixture of gases in response to sudden vehicle deceleration. A directing means directs a flow of gas from containing means into the inflatable occupant restraint. In the preferred embodiment the gases are an inert gas, a fuel gas, and an oxidizer gas. Also, a lean mixture of a fuel gas and oxidizer gas could be used. An improved igniter transmits energy through an imperforate portion of a wall of the containing means to ignite a charge in the containing means. The igniter may include an elongate core disposed in a frangible sheath which is shattered as the core is burned.

RELATED APPLICATION

This application is a continuation-in-part of application Ser. No.07/761,685 filed Sep. 18, 1991 by Jack L. Blumenthal and Nahum Gat andentitled “Apparatus for Inflating a Vehicle Occupant Restraint” nowabandoned. The benefit of the earlier filing data of the aforementionedapplication Ser. No. 07/761,685 has been and hereby is claimed.

FIELD OF THE INVENTION

The present invention relates to a new and improved apparatus forinflating an inflatable device such as a vehicle occupant restraint.

BACKGROUND OF THE INVENTION

Known structures for inflating a vehicle occupant restraint aredisclosed in U.S. Pat. Nos. 3,806,153, 3,868,124 and 3,895,821. In eachof the structures disclosed in these patents, air, or other gas, andsolid gas generating material are stored in a container. Upon theoccurrence of a high rate of vehicle deceleration indicative of acollision, the gas in the container is released to inflate a vehicleoccupant restraint which restrains a vehicle occupant during thecollision. Also, upon the occurrence of a high rate of vehicledeceleration which is indicative of a vehicle collision, the gasgenerating material is ignited. As the gas generating material burns, itforms hot gases or vapors which heat and mix with the stored gas, andthe heated mixture of gases flows into the occupant restraint.

SUMMARY OF THE INVENTION

The present invention provides a new and improved apparatus forinflating an inflatable device such as a vehicle occupant restraint. Theapparatus includes a containing means for receiving gases to provide acombustible mixture of the gases. The apparatus also includes an ignitermeans for igniting the mixture of gases to warm and increase thepressure of gas in the containing means. The apparatus further includesa directing means which directs gas from the containing means to theinflatable device.

Preferably, the mixture of gases includes an inert gas, a flammable fuelgas and an oxidizer gas. The inert gas is preferably nitrogen or argonor a mixture of nitrogen and argon. The fuel gas is preferably hydrogenor methane or a mixture of hydrogen and methane but may be any otherflammable gas. The oxidizer gas is preferably oxygen. Alternatively, theinert gas can be eliminated and a combustible gas mixture that is veryfuel lean could be used. A small amount of an inert tracer gas such ashelium may also be added to assist in leak checking the apparatus.

The containing means may take a variety of different forms. In oneembodiment of the invention, the containing means is a single containerfor containing the inert gas, the fuel gas, and the oxidizer gas as amixture of gases. Alternatively, the single container may contain thevery fuel lean combustible gas mixture.

In another embodiment, a first container contains the fuel gas, a secondcontainer contains the oxidizer gas, and the containing means defines acombustion chamber which receives the fuel gas and oxidizer gas and inwhich the mixture of gases is ignited. In this embodiment the amount ofoxidizer gas used is in excess of a stoichiometric amount to supportcombustion of the fuel gas.

In accordance with the present invention, the rate of inflation of theinflatable device can be controlled to provide a desired volume of theinflatable device at a given time after ignition of the fuel gas. Therate of inflation of and the pressure in the inflatable device can becontrolled by selecting the amount of fuel gas and oxidizer gas toyield, a desired burning rate which in turn determines the predeterminedvolumetric rate of flow of warm gas into the inflatable device.Alternatively or additionally, the rate of inflation can be controlledby flow control orifices or the like through which the gas flows intothe inflatable device. Another technique for controlling the timerequired for inflation is to change the number of locations in thecontaining means at which the fuel gas is ignited.

An improved igniter means is provided for igniting a mixture of gases.The igniter means is operable to transmit energy through an imperforatewall portion of the containing means. The energy transmitted through theimperforate wall portion of the containing means effects ignition ofignitable material in the containing means. Specifically, an ignitablecharge located adjacent to an outer side of the imperforate wall portionof the containing means is ignitable to cause ignition of an ignitablecharge which is disposed adjacent to an inner side of the imperforatewall portion of the containing means. In accordance with another featureof the igniter means, an elongated core in a frangible sheath isdisposed in the containing means. The elongated core is ignited with aresulting shattering of the sheath and spewing of incandescent reactionproducts into the containing means.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present invention will becomeapparent to those skilled in the art to which the present inventionrelates from reading the following specification with reference to theaccompanying drawings, in which:

FIG. 1 is a schematic illustration of one embodiment of the presentinvention;

FIG. 2 is a schematic illustration of a second embodiment of the presentinvention;

FIG. 3 is a schematic illustration of a third embodiment of the presentinvention;

FIG. 4 is a sectional view of part of a vehicle occupant safetyapparatus constructed in accordance with the present invention;

FIG. 5 is a graphic illustration of performance characteristics of atypical vehicle occupant safety apparatus constructed in accordance withthe invention;

FIG. 6 is a schematic illustration of a fourth embodiment of the presentinvention;

FIG. 7 is a schematic illustration of a fifth embodiment of the presentinvention;

FIG. 8 is an enlarged fragmentary schematic illustration of a portion ofthe apparatus of FIG. 7; and

FIG. 9 is a sectional view, taken generally along the line 9—9 of FIG.8.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION Embodiment I

The present invention may be embodied in a number of differentstructures. As representative, FIG. 1 illustrates the present inventionas embodied in a vehicle occupant safety apparatus 10. The vehicleoccupant safety apparatus 10 includes an inflatable vehicle occupantrestraint 12 and apparatus for inflating the vehicle occupant restraint.

Upon the occurrence of a high rate of vehicle deceleration which isindicative of a vehicle collision, the vehicle occupant restraint 12 isinflated to restrain movement of an occupant of the vehicle. Theinflatable vehicle occupant restraint 12 is inflated into a location inthe vehicle between the occupant and certain parts of the vehicle, suchas the steering wheel, instrument panel or the like, before the occupantmoves relative to those parts and forcibly strikes the parts during avehicle collision. The inflated vehicle occupant restraint 12 absorbskinetic energy of the occupant's movement and restrains the occupant'smovement so that the occupant does not forcibly strike parts of thevehicle. Such a vehicle occupant restraint may be inflated by differentgases. Notwithstanding the gas used to inflate the vehicle occupantrestraint 12, the vehicle occupant restraint is commonly referred to asan air bag.

The vehicle occupant restraint 12 is inflated by a flow of gas form acontainer 14. The container 14 has a chamber 16 which holds a mixture 18of gases. The mixture 18 of gases preferably includes a fuel gas, anoxidizer gas for supporting combustion of the fuel gas, and an inertgas. The inert gas is preferably nitrogen, argon or a mixture ofnitrogen and argon. The oxidizer gas is preferably oxygen. The fuel gasis preferably hydrogen, but may be methane, or a mixture of hydrogen andmethane which is a gaseous hydrocarbon.

Alternatively, the mixture of gases in container 14 may be an oxidizergas and a fuel gas in amounts which provide a very fuel lean mixture,i.e., the amount of oxidizer gas exceeds that amount required to supportcombustion of the fuel gas.

The mixture 18 of gases in the container 14 readily combusts, whenignited, but otherwise is not explosive. As such, the mixture 18 ofgases could have many different compositions. The fuel gas may be 2 to16 molar percent of the mixture 18 of gases. The oxidizer gas may be 7to 98 molar percent of the mixture 18 of gases. The balance is inert gaswhich may be 0 to 91 molar percent of the mixture 18 of gases.Preferably, the mixture 18 of gases includes 10-14 molar percenthydrogen, 15-25 molar percent oxygen, and 61-75 molar percent inert gas.

The mixture 18 of gases in the container 14 is normally under pressure.The pressure depends upon such factors as the volume of the vehicleoccupant restraint 12 to be inflated, the time available for inflation,the inflation pressure desired, the volume of the container for themixture 18 of gases, and the percentage of each of the gases in themixture 18 of gases. Normally, the mixture 18 of gases in the container14 may be at a pressure of 500 to 5,000 pounds per square inch (psi).Preferably, the mixture 18 of gases in the container 14 is at a pressureof 1,000 to 3,000 psi. However, the invention is applicable to anymixture of gases regardless of pressure.

In one specific embodiment, the mixture 18 of gases is dry air andhydrogen. The mixture of dry air and hydrogen may range from 86 molarpercent air and 14 molar percent hydrogen to 92 molar percent air and 8molar percent hydrogen. However, it is presently preferred to have arange from 90 molar percent air and 10 molar percent hydrogen to 87molar percent air and 13 molar percent hydrogen.

Upon the occurrence of sudden vehicle deceleration, a decelerationsensor 22, of any known and suitable construction, activates an igniter24 in the chamber 16 to ignite the fuel gas in the mixture 18 of gases.The combustion of the fuel gas is supported by the oxidizer gas. As thefuel gas burns, the pressure in the chamber 16 rises due to warming ofthe gases by the heat of combustion created by burning of the fuel gasand the formation of additional gases or vapors produced by combustionof the fuel gas. After a predetermined time, or when a predeterminedpressure is reached in the chamber 16, an end wall 28 of the container14 bursts, and warm gas flows into the vehicle occupant restraint 12through a flow controller orifice. As the gas flows into the vehicleoccupant restraint 12, the gas inflates the vehicle occupant restraint12 into a predetermined position for restraining a vehicle occupant.

If the amount of hydrogen is less than about 8 molar percent, difficultymay be encountered in igniting the hydrogen. If the amount of hydrogenis more than 14 molar percent, unacceptable pressures and/ortemperatures may be created in the vehicle occupant restraint 12.Preferably, the fuel gas is included in the mixture 18 of gases in anamount so that it is substantially consumed by combustion in thecontainer 14. The vehicle occupant restraint 12 is thus inflated almostexclusively, in the case where inert gas is used, by inert gas,combustion products and any remaining oxidizer gas or, in the case whereinert gas is not used, by the remaining oxidizer gas and combustionproducts.

As the gas flows from the container 14 into the vehicle occupantrestraint 12, the gas expands and cools. In addition, air from theenvironment around the safety apparatus 10 may be aspirated into thevehicle occupant restraint 12 as the vehicle occupant restraint isinflated. This aspirated air will also cool the gas in the vehicleoccupant restraint 12.

Since the fuel gas in the mixture 18 of gases burns to generate heatwhich increases the pressure of the gas in the chamber 16, the totalvolume of gas which must be stored in the container 14 to inflate thevehicle occupant restraint 12 to a desired pressure is minimized.Additionally, since combustion of the fuel gas produces gaseousmaterial, i.e., water vapor, instead of solid material, there is no needfor a particulate filter or the like.

The container 14 in the safety apparatus 10 is shown in greater detailin FIG. 4. As shown in FIG. 4, the container 14 comprises a cylindricaltank 30. The tank 30 defines the chamber 16 containing the mixture 18 ofgases The tank 30 must be made of a material impervious to the gasescontained in the container. Therefore, the tank 30 may be made of asuitable metal, such as steel or aluminum, and may have a glass lining.A cylindrical gas flow diffuser 32 surrounds the tank 30. The diffuser32 has a plurality of gas flow openings 35.

An igniter housing 34 extends through an opening at one end of the tank30, and supports the igniter 24. The igniter 24 can be any one of manyknown types of igniters. Thus, the igniter can be a spark plug, flashbulb igniter (as shown, for example, in U.S. Pat. No. 3,695,179), or apyrotechnic igniter. The specific igniter 24 shown in FIG. 4 is a knownsquib containing a pyrotechnic material which is preferably zirconiumpotassium perchlorate. A single igniter, as shown in FIG. 4, or aplurality of igniters can be used. The percentage of fuel gas in themixture 18 of gases may be varied to facilitate ignition of the fuel gasby the igniter or igniters.

A cylindrical manifold 40 extends through an opening in the end of thetank 30 opposite the igniter 24 and also extends through an adjacentopening in the diffuser 32. A circular end wall 42 of the manifold 40located inside the tank 30 has a centrally located control orifice 44. Acylindrical side wall 46 of the manifold 40 has a circumferentiallyextending array of gas flow openings 48 located between the tank 30 andthe diffuser 32. The end wall 28, shown schematically in FIG. 1, is aburst disk supported inside the manifold 40 between the control orifice44 and the gas flow openings 48.

When the fuel gas in the mixture 18 of gases in the chamber 16 isignited by the igniter 24, combustion of the fuel gas generates heat andgaseous products of combustion which increase the pressure in thechamber 16. When the increasing pressure in the tank 30 reaches apredetermined level, the end wall 28 bursts. Pressurized gas then flowsfrom the chamber 16 through the manifold 40 to the gas flow openings 35in the diffuser 32, and through the gas flow openings 35 into thevehicle occupant restraint 12.

FIG. 5 illustrates graphically the relationship between the pressure inthe chamber 16 and the volume of gas in the vehicle occupant restraint12 during operation of the vehicle occupant safety apparatus 10. Thepressure in the chamber 16 is represented in FIG. 5 by the curve P. Thescale for the curve P is shown on the left side of FIG. 5. The volume ofgas in the vehicle occupant restraint 12 is represented in FIG. 5 by thecurve V. The scale for the curve V is shown on the right side of FIG. 5.At time T₀, the fuel gas in the mixture 18 of gases in the chamber 16 isignited, and the pressure in the chamber 16 begins to increase above thestorage pressure P_(s) as a result of the combustion. At time T₁, theend wall 28 bursts and the pressurized gas begins to flow into thevehicle occupant restraint 12. The volume of gas in the vehicle occupantrestraint 12 then begins to increase, as indicated by the curve V. Thepressure in the chamber 16 initially remains constant of continues torise after the end wall is opened since the combustion process continuesto generate heat and causes the gas mixture to expand at a rate fasterthan the gas flows out through the orifice 44 into the vehicle occupantrestraint 12. As the combustion nears completion, the pressure in thechamber 16 decreases as the pressurized gas moves from the chamber 16into the vehicle occupant restraint 12. As the pressure in the chamber16 decreases, the volume of gas in the vehicle occupant restraint 12increases until the vehicle occupant restraint 12 is fully inflated forthe purpose of restraining a vehicle occupant.

FIG. 5 is merely representative of the operation of a vehicle occupantrestraint inflator in accordance with the present invention. The curvesshown in FIG. 5 can be modified in a number of ways to tailor the volumeversus time curves so that inflation of the vehicle occupant restraintmay be tailored for a specific application for a specific vehicle. Forexample, the time to inflate the vehicle occupant restraint 12 fully canbe reduced by increasing the fuel gas content of the mixture 18 of gasesand/or by increasing the oxidizer gas content. Additionally oralternatively, the number of locations at which the fuel gas in themixture 18 of gases is ignited and/or the area of the control orifice 44can be increased. Further, combination of these changes can be used todecrease the time to inflate the vehicle occupant restraint 17.Conversely, the time to inflate the vehicle occupant restraint 12 fullycan be increased by, for example, decreasing the fuel gas content and/orthe oxidizer gas content of the mixture 18 of gases.

Embodiment I described above is the preferred embodiment of the presentinvention. Below are descriptions of other embodiments of the presentinvention which are alternative ways to practice the invention.

Embodiment II

Since the embodiment of the invention illustrated in FIG. 2 is generallysimilar to the embodiment of the invention illustrated in FIG. 1,similar numerals are utilized to designate similar components, thesuffix letter “a” is added to the numerals designating the components ofthe embodiment of the invention illustrated in FIG. 2 to avoidconfusion.

A vehicle safety apparatus 10a (FIG. 2) includes an inflatable vehicleoccupant restraint 12a which is inflated by a flow of a gas from acontainer 14a. The container 14a has a chamber 16a in which a mixture18a of gases is held. Like the mixture 18, the mixture 18a of gasesincludes a fuel gas, an oxidizer gas for supporting combustion of thefuel gas, and inert gas. Alternatively, the mixture 18a of gases may bea very fuel lean combustible gas mixture of a fuel gas and an oxidizergas. Also, the mixture 18a of gases may be under pressure.

Upon the occurrence of a high rate of vehicle deceleration, adeceleration sensor 22a activates an opener 60 to puncture mechanicallyan end wall 28a of the container 14a. The opener 60 can comprise apiston which is moved against the end wall 28 by an explosive charge.Preferably, at the same time, the deceleration sensor 22a activates anigniter 24a to ignite the fuel gas in the mixture 18a of gases. Thus, inthe embodiment of the invention illustrated in FIG. 2, the container 14ais opened by the opener 60 simultaneously with ignition of the fuel gasin the mixture 18a of gases by the igniter 24a. Alternatively, themixture of gases may be ignited a short time after the puncturing of theend wall in order to get a slightly “softer” of slower initial flow ofgas into the vehicle occupant restraint. Additionally, the mixture ofgases may be ignited prior to opening the end wall 28 28a. As the fuelgas burns, the gas in the chamber 16a is heated. The heated gas flowsfrom the chamber 16a through the opening in the end wall 28a of thecontainer 14a into the vehicle component restraint 12a to inflate thevehicle occupant restraint.

The mixture 18a of gases could have many different compositions. Thepreferences for composition of the mixture 18a of gases are the same asthose described above concerning the mixture 18. In one specificembodiment, the mixture 18a of gases includes dry air to whichapproximately eleven molar percent hydrogen gas is added as the fuelgas. Prior to opening of the container 16a by the opener 60 and ignitionof the hydrogen gas in the mixture 18a of gases, the mixture 18a ofgases is held in the container 14a at a pressure of approximately 2,000psi. The preferences for storage pressure for the mixture 18a of gasesalso are the same as those described above concerning the mixture 18.

Embodiment III

A third embodiment of the invention is illustrated in FIG. 3. Since thecomponents of this embodiment of the embodiments of the inventionillustrated in FIG. 1 and 2, similar numerals are utilized to designatesimilar components, the suffix letter “b” is associated with thenumerals of FIG. 3 to avoid confusion.

A vehicle safety apparatus 10b (FIG. 3) includes a vehicle componentrestraint 12b which is inflated by a flow of gas from a container 14b torestrain movement of an occupant of a vehicle. The container 14bincludes an upper compartment 70 having an end wall 28b and a lowercompartment 72. The upper and lower compartments 70 and 72 are separatedfrom each other by an intermediate wall 74. The upper compartment 70contains a pressurized gas 78 which is not combustible. The lowercompartment 72 contains a pressurized mixture 80 of gases. The mixture80 of gases preferably contains a fuel gas, an inert gas and an oxidizergas for supporting combustion of the fuel gas in a mixture with theinert gas. Alternatively, the mixture 80 of gases may be an oxidizer gasand a fuel gas in amounts which provide a very fuel lean mixture.

Upon the occurrence of sudden vehicle deceleration, a decelerationsensor 22b activates an opener 60b to puncture the container end wall28b mechanically. Since the gas 78 in the upper compartment 70 is heldunder pressure, the gas 78 flows from the upper compartment 70 into thevehicle occupant restraint 12b when the end wall 28b is punctured.

As the gas 78 flows from the upper compartment 70 into the vehicleoccupant restraint 12b, the pressure in the upper compartment 70 isreduced. Consequently, the pressure differential between the mixture 80of gases in the lower compartment 72 and the gas 78 in the uppercompartment 70 increases. When a predetermined pressure differential hasbeen established between the gases in the upper and lower compartments70 and 72, the intermediate wall 74 bursts to connect the lowercompartment 72 in fluid communication with the upper compartment 70.This results in the lower compartment 72 being connected in fluidcommunication with the vehicle occupant restraint 12b through the uppercompartment 70.

Bursting of the intermediate wall 74 by the pressure differential isdetected by a sensor 86. Alternatively, the sensor 86 may detect thatthe wall 74 has deflected beyond a certain preset position. Upondetecting that the intermediate wall 74 has burst or deflected beyond acertain preset position, the sensor 86 activates an igniter 88 to ignitethe fuel gas in the mixture 80 of gases. Ignition and the resultingburning of the fuel gas in the mixture 80 of gases heats the gas in thelower compartment 72. As the gas in the lower compartment 72 is heated,the pressure in the lower compartment 72 increases. Therefore, the rateof flow of gas through the intermediate wall. 74 and the end wall 28b tothe vehicle occupant restraint 12b increases and the volume of gasavailable for inflating the vehicle occupant restraint 12b increases.

The upper compartment 70 may be filled with dry air at a pressure of2,000 psi. The mixture of gases in the lower compartment 72 could havemany different composition at different pressures. The lower compartment72 may be filled with a mixture of gases at a pressure of 2,000 psi. Themixture 80 of gases in the lower compartment 72 may consist of 85 to 90molar percent dry air and 10 to 15 molar percent hydrogen gas. It iscontemplated that the upper compartment 70 could be filled with nitrogengas and the lower compartment 72 could be filled with a mixture ofnitrogen gas, hydrogen gas, and an oxidizer gas. The mixture of gases inthe lower compartment 72 could also have any composition and/or storagepressure described above concerning the mixture 18 of gases in theembodiment of FIG. 1.

Although it is preferred to connect the lower compartment 72 in fluidcommunication with the upper compartment 70 and the vehicle occupantrestraint 12b by rupturing the intermediate wall 74 when a predeterminedpressure differential is established between the upper and lowercompartments 70 and 72, the upper and lower compartments 70 and 72 ofthe container 14b could be connected in fluid communication in adifferent manner. For example, an opener, similar to the opener 60b,could be provided to puncture the intermediate wall 74 mechanically.Operation of the opener to puncture the intermediate wall 74 andsimultaneous operation of the igniter 88 to ignite the fuel gas in themixture 80 of gases would take place at a predetermined time intervalafter the deceleration sensor 22b detects the occurrence of suddenvehicle deceleration.

Embodiment IV

A fourth embodiment of the invention is illustrated in FIG. 6. In thisembodiment, hydrogen is stored under pressure in a container 100, andoxygen is stored under pressure in a container 101. Container 100 has anoutlet 102 in communication with a combustion chamber 104 defined by acontaining means 106. The container 101 also has an outlet 108 incommunication with the combustion chamber 104.

The outlet 102 has a flow control orifice 110 and a burst disk 112. Whenthe burst disk 112 opens, hydrogen flows into the combustion chamber 104of the containing means 106. The flow of hydrogen is controlled, inpart, by the area of the flow control orifice 110. The outlet 108 has aflow control orifice 114 and a burst disk 116. When the burst disc 116opens, oxygen flows into the combustion chamber 104 of the containingmeans 106. The flow of oxygen is controlled, in part, by the area of theflow control orifice 114. Thus, when the burst disks 112, 116 open, thecontaining means 106 receives gases, i.e., hydrogen and oxygen, toprovide a combustible mixture of hydrogen and oxygen.

A suitable igniter 130 is associated with the containing means 106. Theigniter 130, when actuated, ignites the mixture of gases in thecombustion chamber 104 of the containing means 106 to increase thepressure and warm the gas in the combustion chamber 104. The gas isdirected from the combustion chamber 104 through a flow control orifice131 and an outlet conduit 132 into the inflatable vehicle occupantrestraint 134. The flow control orifice 131 in part controls the gasflow rate to the inflatable occupant restraint and the pressure in thecombustion chamber 104. The inflatable vehicle occupant restraint 134may be as described above in embodiment I.

A suitable opener device 140 is associated with the burst disk 112. Whenthe opener device 140 is actuated, the burst disk 112 is opened. Also, asuitable opener device 142 is associated with burst disk 116. When theopener device 142 is actuated, the burst disk 116 is opened.

The opener devices 140, 142 are actuated by a vehicle decelerationsensor sensing rapid vehicle deceleration as indicative of a collision.As a result, the hydrogen and oxygen flow into and mix together incombustion chamber 104. The vehicle deceleration sensor also actuatesthe igniter 130 which, in turn, ignites the mixture of hydrogen andoxygen in the combustion chamber 104. Ignition of the mixture of gasesin the combustion chamber 104 warms the gas and increases the pressureof the gas in the combustion chamber 104. The gas then flows into thevehicle occupant restraint 134.

The amount of hydrogen and oxygen which are stored in containers 100,101 may vary. It is desired that the amount of hydrogen in thecombustion chamber 104 is approximately 10 molar percent of the total ofthe hydrogen and oxygen in the combustion chamber 104 and the amount ofoxygen in the combustion chamber 104 is approximately 90 molar percentof the total of the hydrogen and oxygen in the combustion chamber 104.This provides oxygen substantially in excess of that needed to supportcombustion of the hydrogen. Thus, the vehicle occupant restraint isinflated by the oxygen and products of combustion of the mixture of gasin the combustion chamber 104. The products of combustion include watervapor.

Embodiment V

A fifth embodiment of the invention is illustrated in FIGS. 7, 8 and 9.Since the components of this embodiment of the invention are generallysimilar to the components of the embodiment of the invention illustratedin FIGS. 1-4, similar numerals will be utilized to designate similarcomponents, the suffix letter “c” is associated with the numerals ofFIGS. 7-9 to avoid confusion.

A vehicle safety apparatus 10c (FIG. 7) includes a vehicle occupantrestraint (not shown) which is inflated by a flow of gas from acontainer 14c. The container 14c has a chamber 16c which holds a mixture18c of gases. The mixture 18c of gases preferably includes a fuel gas,an oxidizer gas for supporting combustion of the fuel gas, and an inertgas. Alternatively, the mixture 18c of gases in the container 14c may bean oxidizer gas and a fuel gas in amounts which provide a very fuel leanmixture, i.e., the amount of oxidizer gas exceeds the amount required tosupport combustion of the fuel gas.

The mixture 18c of gases in the container 14c combusts, when ignited,but otherwise is not explosive. The mixture 18c of gases in thecontainer 14c is normally under pressure. The mixture 18c of gases hasthe same composition as the mixture 18 of gases described in conjunctionwith the embodiment of the invention illustrated in FIGS. 1-4.

Upon the occurrence of sudden vehicle deceleration, a decelerationsensor (not shown), of any known and suitable construction, transmits asignal over conductors 150 and 152 to activate an igniter 24c.Activation of the igniter 24c ignites the fuel gas in the mixture 18c ofgases. The combustion of the fuel gas in the mixture 18c is supported bythe oxidizer gas. As the fuel gas burns, the pressure in the chamber 16crises due to heat supplied by the igniter 24c and by the burning of thefuel gas.

When a predetermined pressure is reached in the chamber 16c, or after apredetermined time, a burst disk (not shown) in a burst disk assembly156, bursts and warm gas flows into the vehicle occupant restraintthrough one or more flow controlling orifices. As the gas flows into thevehicle occupant restraint, the gas inflates the vehicle occupantrestraint into a predetermined position for restraining a vehicleoccupant

In accordance with a feature of this embodiment of the invention, theigniter 24c is operable to transmit energy through an imperforate wallportion 160 (FIG. 8) of the container 14c to effect ignition of themixture 18c of gases in the container 14c. The igniter 24c includes anignitable outer charge 164 disposed adjacent to an importance outer sidesurface 166 of the wall portion 160. The outer charge 164 is enclosed bya cylindrical metal housing 170 which is welded to the imperforate outerside 166 of the wall portion 160. The outer charge 164 engages theimperforate outer side 166 of the wall portion 160.

An ignitable inner charge 174 is disposed in engagement with animperforate inner side 176 of the wall portion 160. The inner charge 174is enclosed in a cylindrical metal housing 178 which is welded to theimperforate inner side 176 of the wall portion 160. A circular sealingdisk 186 blocks exposure of the inner charge 174 to the mixture of gasesin the chamber 18c.

In one specific embodiment of the invention, the ignitable outer charge164 may be RDX (Royal Danish Explosive). However, HMX (Her Majesty'sExplosive) could be utilized if desired. The outer charge 164 and innercharge 174 both have a cylindrical configuration with a diameter ofabout 0.100 inches.

In the specific illustrated embodiments of the invention, the innercharge 174 is in two sections, a cylindrical outer section 180 and acylindrical inner section 182. The outer section 180 is made ofpentaerythritol tetranitrate. The inner section 182 is made of boronpotassium nitrate (BKNO₃). In this specific embodiment of the invention,the cylinder 14c is formed of 304 stainless steel vacuum arc remelt. Theportion 160 of the cylinder wall between the outer charge 164 and theinner charge 174 has a thickness of about 0.085 inches.

The igniter 24c also includes an elongated ignition line 192. Theignition line 193 has an end portion 194 disposed adjacent to the innercharge 174 and sealing disk 186. The end portion 194 (FIG. 8) of theignition line 192 is telescopically mounted in the housing 178 so thatthe end of the ignition line 192 is in abutting engagement with thesealing disk 186 and is closely adjacent to the inner charge 174. Theignition line 192 has a longitudinal central axis which is coincidentwith a longitudinal central axis of the container 14c. The ignition line192 extends from the housing 178 through a central portion of thecontainer 14c toward a right (as viewed in FIG. 7) end portion of thecontainer. Thus, the ignition line 192 has an end portion 196 (FIG. 7)disposed adjacent to the burst disk assembly 156.

Although the end portion 196 of the ignition line 192 is shown in FIG. 7as being unsupported, a support could be provided on the inner side ofthe burst disk assembly 156 or the side wall of the container 14c. Also,if desired, the ignition line 192 could be offset to one side of thecentral axis of the container 14c.

The ignition line 192 (FIG. 8) includes a cylindrical sheath 202. Thesheath 202 is fabricated of a frangible material such as plastic,ceramic, or a composite material. An elongated core 204 is disposedwithin the sheath 202. The core 204 is formed of non-detonative,ignitive material and has a high heat of combustion.

The core 204 is formed in three cylindrical strands 206, 208, and 210(FIG. 9) which are enclosed by an imperforate cylindrical side wall ofthe sheath 202. The strands 206, 208 and 210 include longitudinallyextending support elements 214 coated with a non-detonative ignitivemixture of powdered fuel, oxidant and a suitable binder. The supportelements 214 are fabricated of a material such as glass fibers, metal ora polymeric material.

The area bounded by the sheath 202 is larger than the transversecross-sectional area of the core 204. Therefore, there are spaces 220between the core strands 206, 208, 210 and the sheath 202 and betweenthe core strands themselves. An adherent powdery ignition layer 222,composed of the same material as the strands 206, 208, 210, is disposedon the inner side of the sheath 202.

The ignition line 192 is commercially available from ExplosiveTechnology in Fairfield, Calif. and is known as ITLX. Although theignition line 192 has been disclosed as having a cylindrical sheath 202and a core 204 formed of three strands 206, 208 and 210, it iscontemplated that the ignition line 192 could have many differentconstructions, such as those shown in U.S. Pat. No. 4,220,087, issuedSep. 7, 1980 and entitled “Linear Ignition Fuse”.

Upon the occurrence of sudden vehicle deceleration, the decelerationsensor (not shown) transmits a signal over the lines 150 and 152 toeffect ignition of the outer charge 164. Ignition of the outer charge164 results in vibration of the imperforate wall portion 160 of thecontainer 14c. The force transmitted by vibration of the wall portion160 between the charges 164 and 174 causes ignition of the section 180of the inner charge 174. The ignites the charge section 182. Ignition ofthe charge sections 180 and 182 of the inner charge 174 destroys thesealing disk 186 and ignites the core 204 at the end portion 194 of theignition line 192.

Upon ignition of the core 204, the ignition reaction is propagated at avery high speed, on the order of 1,000-5,000 meters per second, alongthe ignition line 192. As the reaction travels along the ignition line192, the sheath 202 is shattered. Shattering the sheath 202 results tosmall, incandescent particles of reaction products being radicallyprojected from the ignition line 192.

Heat provided by the ignition of the ignition line 192 quickly heats thegas immediately adjacent to the surface of the sheath 202 to atemperature of approximately 1,000° F. This ignites the combustiblemixture 18c of gases in the chamber 16c. In addition, the small,incandescent particles of reaction products projected from the ignitionline 192 as the sheath 202 is shattered are effective to ignite themixture 18c of combustible gases at locations speed from the ignitionline.

Thus, the ignition line 192 performs the dual functions of heating themixture 18c of gases in the container 14c and of igniting the mixture ofgases. Since the ignition line 192 adds a substantial amount of heat tothe mixture 18c of gases, a lower amount of the fuel gas is requiredthan would be the case if a different type of igniter was utilized.

From the above description of the invention, those skilled in the artwill perceive applications, improvements, changes and modifications tothe present invention. For example, the gas in the container 101 (FIG.6) might include an inert gas, such as nitrogen, as well as oxygen. Inan alternative to the FIG. 6 embodiment, an inert gas might be storedunder pressure in a separate container similar to the container 100 and101. The apparatus of the present invention may also be used forinflating devices other than an inflatable vehicle occupant restraintknown as an air bag. For example, the apparatus of the present inventionmay be used to inflate an inflatable vehicle seat belt, a raft, anescape chute, etc. Such applications, improvements, changes andmodifications within the skill of the art are intended to be covered bythe appended claims.

Having described the invention, the following is claimed:
 1. Anapparatus for inflating a vehicle occupant restraint, said apparatuscomprising: gas containing means having a single cavity for containing amixture of gases; a mixture of gases in said single cavity consisting ofa combustible mixture of gases comprising the only stored gases forfilling the vehicle occupant restraint; igniter means which ignites thecombustible mixture of gases in said single cavity and forms an occupantrestraint inflating gas from said combustible mixture of gases, saidoccupant restraint inflating gas comprising the ignited combustiblemixture of gases; and directing means which directs said occupantrestraint inflating gas, which comprises the ignited combustible mixtureof gases, from said single cavity to said vehicle occupant restraint toinflate said vehicle occupant restraint.
 2. An apparatus as defined inclaim 1 further including a vehicle deceleration sensor and wherein saidigniter means includes means for igniting the mixture of gases inresponse to sudden vehicle deceleration sensed by said decelerationsensor.
 3. An apparatus as defined in claim 1 wherein said mixture ofgases includes an inert gas, a fuel gas, and an oxidizer gas forsupporting combustion of said fuel gas.
 4. An apparatus as defined inclaim 3 wherein said containing means comprises a single container forcontaining said inert gas, said fuel gas, and said oxidizer gas.
 5. Anapparatus as defined in claim 4 wherein the containing means is at apressure of approximately 500 to 5,000 psi.
 6. An apparatus as definedin claim 3 wherein the relative amounts of inert gas, fuel gas, andoxidizer gas are selected to yield upon combustion of the fuel gas apredetermined volumetric flow rate of heated gas to inflate the vehicleoccupant restraint.
 7. An apparatus as defined in claim 3 wherein saidfuel gas is selected from the group consisting of hydrogen and a gaseoushydrocarbon, said oxidizer gas is oxygen, and said inert gas is selectedfrom the group consisting of nitrogen and argon.
 8. An apparatus asdefined in claim 3 wherein said fuel gas is hydrogen comprising about 10to 14 molar percent of the mixture of said gases, said oxidizer gas isoxygen comprising about 15 to 25 molar percent of the mixture of saidgases, and said inert gas is nitrogen comprising about 61-75 molarpercent of the mixture of said gases.
 9. An apparatus as defined inclaim 1 wherein said mixture of gases consists of a lean mixture of afuel gas and an oxidizer gas.
 10. An apparatus as defined in claim 9wherein said containing means comprises a single container for saidmixture of gases of said fuel gas and said oxidizer gas.
 11. Anapparatus as defined in claim 9 further including a first container forsaid fuel gas, a second container for said oxidizer gas, and means fordirecting fuel gas and oxidizer gas from said first and secondcontainers into a combustion chamber defined by said containing means.12. An apparatus as defined in claim 11 wherein said igniter meansignites the mixture of gases in said combustion chamber.
 13. Anapparatus as defined in claim 12 wherein said directing means directsgas from said combustion chamber into said vehicle occupant restraint.14. An apparatus as defined in claim 1 wherein said igniter meansincludes an elongate heat source which extends from one end portion ofsaid containing means through a central portion of said containingmeans.
 15. An apparatus as set forth in claim 14 wherein said containingmeans has a longitudinal central axis, said elongate heat source beingdisposed on the longitudinal central axis of said containing means. 16.An apparatus as set forth in claim 1 wherein said igniter means includesan elongate core disposed in a frangible sheath in said containingmeans, and means for initiating burning of said core with a resultantshattering of said sheath and spewing of incandescent reaction productsinto the combustible mixture of gases along the length of said elongatedcore.
 17. An apparatus as set forth in claim 1 wherein said containingmeans includes an imperforate wall portion, said igniter means includesa first ignitable charge disposed adjacent to a first side of saidimperforate wall portion and a second ignitable charge disposed adjacentto a second side of said imperforate wall portion.
 18. An apparatus asset forth in claim 1 wherein said containing means includes animperforate wall portion, said igniter means includes a source of energydisposed adjacent to a first side of said imperforate wall portion, andmeans disposed adjacent to a second side of said imperforate wallportion and actuatable due to energy transmitted through saidimperforate wall portion to effect ignition of the combustible mixtureof gases.
 19. An apparatus for inflating a vehicle occupant restraint asdefined in claim 1 wherein said igniter means forms an occupantrestraint inflating gas consisting of the ignited combustible mixture ofgases and said directing means directs said occupant restraint inflatinggas consisting of said ignited combustible mixture of gases to inflatesaid vehicle occupant restraint.
 20. An apparatus for inflating avehicle occupant restraint, said apparatus comprising: a containerhaving an imperforate wall portion with inner and outer sides; anignitable gaseous material consisting of a combustible mixture of gasesdisposed in said container; igniter means for igniting the combustiblemixture of gases, said igniter means igniting the combustible mixture ofgases in said container to effect a flow of the ignited combustiblemixture of gases from said container, said igniter means including asource of energy disposed adjacent to the outer side of said imperforatewall portion of said container and means disposed adjacent to the innerside of said imperforate wall portion of said container and actuatabledue to the energy transmitted through said imperforate wall portion ofsaid container to effect ignition of the ignitable gaseous material insaid container, and directing means for directing the ignitedcombustible mixture of gases from said container to said vehicleoccupant restraint to inflate said vehicle occupant restraint.
 21. Anapparatus as set forth in claim 20 wherein said source of energyincludes a first ignitable charge and said means disposed adjacent tothe inner side portion of said imperforate wall portion of saidcontainer includes a second ignitable charge which is ignited under theinfluence of vibrations transmitted through said imperforate wallportion of said container in response to ignition of said firstignitable charge.
 22. An apparatus as set forth in claim 21 wherein saidigniter means includes an elongate heat source which extends from alocation adjacent to said second ignitable charge through a centralportion of said container to enable heat to be transferred from saidelongate heat source to the ignitable material along the length of saidelongate heat source.
 23. An apparatus as set forth in claim 22 whereinsaid container has a longitudinal central axis, said elongate heatsource being disposed on the longitudinal central axis of saidcontainer.
 24. An apparatus as set forth in claim 20 wherein saidigniter means includes an elongate core disposed in a frangible sheathin said container, said means disposed adjacent to the inner side ofsaid imperforate wall being operable to initiate burning of said corewith a resultant shattering of said sheath and spewing of incandescentreaction products into the ignitable material in said container.
 25. Anapparatus as set forth in claim 24 wherein said container has alongitudinal central axis, said elongate core and frangible sheath beingdisposed on the longitudinal central axis of said container.
 26. Anapparatus as set forth in claim 24 wherein said elongate core andfrangible sheath extend from one end portion of said container through acentral portion of said container to enable incandescent reactionproducts to be spewed toward said ignitable material in at least the oneend portion and central portion of said container.
 27. An apparatus forinflating a vehicle occupant restraint, said apparatus comprising:containing means including a gaseousa container storing a mixture ofgases consisting ofincluding a fuel gas, an inert gas and an oxidizergas; igniter means for igniting the fuel gas and which ignites the fuelgas in said containing means to heat the mixture of gases in saidcontaining means; container; and directing means for directing theheated mixture of gases from said containing means container to saidvehicle occupant restraint to inflate said vehicle occupant restraint.28. An apparatus for inflating a vehicle occupant restraint, saidapparatus comprising: containing means for containing a combustible,mixture of gases; a combustible, mixture of gases in said containingmeans; means separate from and independent of said combustible mixtureof gases for opening said containing means and for igniting thecombustible mixture of gases to heat the gases in said containing means;and directing means for directing the heated mixture of gases from saidcontaining means to said vehicle occupant restraint to inflate saidvehicle occupant restraint.
 29. A method of inflating a vehicle occupantrestraint, said method comprising: providing a mixture of gasesconsisting of a combustible mixture of gases in a single cavity in acontainer, said combustible mixture of gases being the only stored gasesfor inflating the vehicle occupant restraint; igniting the combustiblemixture of gases in the single cavity to form an occupant restraintinflating gas from said combustible mixture of gases and comprising theignited combustible mixture of gases; and directing the occupantrestraint inflating gas, which comprises the ignited combustible mixtureof gases, from the single cavity to the vehicle occupant restraint toinflate the vehicle occupant restraint.
 30. A method as set forth inclaim 29 wherein said step of providing a combustible mixture of gasesincludes providing an inert gas, a fuel gas and an oxidizer gas, saidstep of igniting the combustible mixture of gases includes burning thefuel gas.
 31. A method as set forth in claim 29 wherein said step ofproviding a combustible mixture of gases includes the step of storing afuel gas in one container, storing an oxidizer gas in another container,and mixing the fuel and oxidizer gases to form the combustible mixtureof gases in response to sudden vehicle deceleration.
 32. A method as setforth in claim 29 further including the step of sensing the occurrenceof sudden vehicle deceleration and performing said step of igniting thecombustible mixture of gases in response to performance of said step ofsensing the occurrence of sudden vehicle deceleration.
 33. A method asset forth in claim 29 further including the step of burning in thecontainer at least a portion of one of the gases in the combustiblemixture of gases.
 34. A method as set forth in claim 29 wherein saidstep of igniting the combustible mixture of gases in the containerincludes transmitting energy through an imperforate portion of a wall ofthe container.
 35. A method as set forth in claim 29 wherein said stepof igniting the combustible mixture of gases in the container includesigniting a first charge disposed outside of the container, and ignitinga second charge disposed inside the container under the influence offorce transmitted through an imperforate wall portion of the containerfrom the first charge to the second charge.
 36. A method as set forth inclaim 29 wherein said step of igniting the combustible mixture of gasesin the container includes spewing incandescent materials into themixture of gases in the container along an elongate path extending fromone end portion of the container through a central portion of thecontainer.
 37. A method of inflating a vehicle occupant restraint asdefined in claim 29 wherein said step of forming an occupant restraintinflating gas includes forming an occupant restraint inflating gasconsisting of the ignited combustible mixture of gases.
 38. A method ofinflating a vehicle occupant restraint, said method comprising the stepsof: providing a gaseousstoring a mixture of gases in a container, saidmixture of gases consisting ofincluding a fuel gas, an inert gas and anoxidizer gas; igniting the fuel gas in the container to heat the mixtureof gases in the container; and directing the mixture of gases from thecontainer to the vehicle occupant restraint to inflate the vehicleoccupant restraint.
 39. A method of inflating a vehicle occupantrestraint, said method comprising the steps of: providingstoring acombustible mixture of gases in a container; providing a means separatefrom and independent of the combustible mixture of gases for opening thecontainer; opening the container by said means separate from andindependent of the combustible mixture of gases; igniting thecombustible mixture of gases to heat the gases in the container;directing the heated mixture of gases from the container to the vehicleoccupant restraint to inflate the vehicle occupant restraint.
 40. Anapparatus for inflating a vehicle occupant restraint, said apparatuscomprising: gas containing means having a chamber for containing amixture of gases; a mixture of gases in said chamber consisting of ahomogeneous, combustible mixture of gases for filling the vehicleoccupant restraint, said combustible mixture of gases including anignitable fuel gas and being a fuel gas lean mixture; igniter meanswhich ignites the combustible mixture of gases in said chamber and formsan occupant restraint inflating gas from said combustible mixture ofgases, said occupant restraint inflating gas comprising the ignitedcombustible mixture of gases; and directing means for directing saidoccupant restraint inflating gas, which comprises the ignitedcombustible mixture of gases, from said chamber to said vehicle occupantrestraint to inflate said vehicle occupant restraint.
 41. An apparatusas defined in claim 40 wherein said igniter means forms an occupantrestraint inflating gas consisting of the ignited combustible mixture ofgases.
 42. A method of inflating a vehicle occupant restraint, saidmethod comprising: providing a mixture of gases consisting of ahomogeneous, combustible mixture of gases in a chamber in a container,said combustible mixture of gases being for inflating the vehicleoccupant restraint, said combustible mixture of gases including anignitable fuel gas an being a fuel gas lean mixture; igniting thecombustible mixture of gases to form an occupant restraint inflating gasfrom said combustible mixture of gases and comprising the ignitedcombustible mixture of gases; and directing the occupant restraintinflating gas, which comprises the ignited combustible mixture of gases,from the container to the vehicle occupant restraint to inflate thevehicle occupant restraint.
 43. A method as defined in claim 42 whereinsaid step of forming an occupant restraint inflating gas includesforming an occupant restraint inflating gas consisting of the ignitedcombustible mixture of gases.
 44. An apparatus for inflating a vehicleoccupant restraint, said apparatus comprising: first and second separatecontainers for containing gas; a fuel gas in said first container; anoxidizer gas in said second container; a containing means for receivingsaid fuel gas and said oxidizer gas from said first and second separatecontainers when said fuel gas and said oxidizer gas are released fromsaid first and second containers; means for releasing said fuel gas andsaid oxidizer gas from said first and second containers for flow intosaid containing means and providing a combustible mixture of gases insaid containing means; igniter means for igniting the combustiblemixture of gases in said containing means; and directing means fordirecting the ignited combustible mixture of gases from said containingmeans to said vehicle occupant restraint to inflate the vehicle occupantrestraint.
 45. A method of inflating a vehicle occupant restraint, saidmethod comprising: providing first and second separate containers forcontaining gas; storing a fuel gas in said first container; storing anoxidizer gas in said second container; providing a containing means forreceiving said fuel gas and said oxidizer gas from said first and secondseparate containers when said fuel gas and said oxidizer gas arereleased from said first and second containers; releasing said fuel gasand said oxidizer gas from said first and second containers for flowinto said containing means and providing a combustible mixture of gasesin said containing means; igniting the combustible mixture of gases insaid containing means; and directing the ignited combustible mixture ofgases from said containing means to said vehicle occupant restraint toinflate the vehicle occupant restraint.
 46. An apparatus for inflating avehicle occupant restraint, said apparatus comprising: first meansdefining a first chamber for containing a first gas; second meansdefining a second chamber for containing a second gas; a first gas insaid first chamber; a second gas comprising a combustible mixture ofgases in said second chamber; means for releasing at different times thefirst and second gases for flow from said first and second chambers atsaid different times; igniter means for igniting said combustiblemixture of gases; and directing means for directing said first gas andsaid ignited combustible mixture of gases into the vehicle occupantrestraint.
 47. A method of inflating a vehicle occupant restraint, saidmethod comprising the steps of: storing a first gas in a first chamber;storing a second gas in a second chamber, said second gas comprising acombustible mixture of gases; releasing at different times the first andsecond gases for flow from said first and second chambers at saiddifferent times; igniting said combustible mixture of gases; anddirecting said first gas and said ignited combustible mixture of gasesinto the vehicle occupant restraint.
 48. An apparatus for inflating avehicle occupant restraint, said apparatus comprising: first meansdefining a first chamber for containing a first gas; second meansdefining a second chamber for containing a second gas; a first gas insaid first chamber; a second gas comprising a combustible mixture ofgases in said second chamber; first actuatable opener means, for whenactuated, opening said first chamber to enable said first gas to flowtherefrom; second actuatable opener means separate from said firstactuatable opener means for opening said second chamber to enable saidsecond gas to flow therefrom; igniter means for igniting saidcombustible mixture of gases; and directing means for directing saidfirst gas into the vehicle occupant restraint and for directing theignited combustible mixture of gases into the vehicle occupantrestraint.
 49. An apparatus for inflating a vehicle occupant restraint,said apparatus comprising: first means defining a first chamber forcontaining a first gas; second means defining a second chamber, largerthan said first chamber, for containing a second gas; a first gas insaid first chamber; a second gas comprising a combustible mixture ofgases in said second larger chamber; actuatable means for, whenactuated, enabling said first and second gases to flow from said firstand second chambers; igniter means for igniting said combustible mixtureof gases; and directing means for directing said first gas into thevehicle occupant restraint and for directing the ignited combustiblemixture of gases into the vehicle occupant restraint.
 50. An apparatusfor inflating a vehicle occupant restraint, said apparatus comprising: acontainer structure defining a combustion chamber, said combustionchamber being bounded by container walls including a non-rupturable tankwall and a rupturable closure wall, said closure wall releasing said gasto exit said combustion chamber upon rupturing of said closure wall; acombustion mixture of gases stored in said container structure, saidmixture of gases including a fuel gas, an oxidizer gas, and an inertgas; igniter means for igniting and heating said stored fuel gas insidesaid combustion chamber upon the occurrence of a vehicle collision, saidfuel gas, when ignited, heating said combustible mixture of gases; anddirecting means for directing inflation gas from said containerstructure toward the vehicle occupant restraint to inflate therestraint.
 51. An apparatus as defined in claim 50 wherein said fuel gasis selected from the group consisting of hydrogen and gaseoushydrocarbons.
 52. An apparatus as defined in claim 50 wherein said fuelgas is stored inside said combustion chamber.
 53. An apparatus asdefined in claim 52 wherein said combustion chamber stores a combustiblemixture of gases comprising said fuel gas and an oxidizer gas.
 54. Anapparatus as defined in claim 53 wherein said combustible mixture ofgases comprises a fuel lean mixture of said fuel gas and said oxidizergas.
 55. An apparatus as defined in claim 53 wherein said combustiblemixture of gases further includes an inert gas.
 56. An apparatus asdefined in claim 53 wherein said combustible mixture of gases comprisesabout 10-14 molar percent of said fuel gas, about 15-25 molar percent ofsaid oxidizer gas, and about 61-75 molar percent of an inert gas.
 57. Anapparatus as defined in claim 50 wherein said fuel gas is stored outsidesaid combustible chamber.
 58. An apparatus as defined in claim 57wherein said container structure further defines a compartment which isseparated from said combustion chamber by another rupturable closurewall, said compartment containing an oxidizer gas.
 59. An apparatus asdefined in claim 58 wherein said compartment further contains said fuelgas.
 60. An apparatus as defined in claim 50 further comprising anoxidizer gas stored in said container structure separately from saidfuel gas, said container structure including means for rupturing toallow said oxidizer gas to mix with said fuel gas to form a combustiblemixture of gases upon the occurrence of a vehicle collision.
 61. Anapparatus as defined in claim 60 further comprising an inert gas storedin said container structure separately from said fuel gas and saidoxidizer gas.
 62. An apparatus as defined in claim 61 wherein saidrupturable means allows said inert gas to mix with said oxidizer gaswhereby warm inflation gas is formed upon heating of said inert gas withheat of combustion created by burning of said fuel gas in a combustiblemixture with said oxidizer gas.
 63. An apparatus as defined in claim 62wherein said rupturable means allows said inert gas to mix with saidfuel gas before said fuel gas is ignited.
 64. An apparatus as defined inclaim 50 wherein said igniter means comprises means for igniting saidfuel gas by transmitting energy from an energy source to said fuel gasthrough an imperforate wall portion of said container structure.
 65. Anapparatus as defined in claim 50 wherein said igniter means includesmeans for igniting said fuel gas by spewing incandescent materials intosaid fuel gas from an elongate combustible means for generating saidincandescent materials.
 66. A method of inflating a vehicle occupantrestraint, said method comprising the steps of: storing inflation gas ina container structure having a combustion chamber with an outlet openingand a rupturable closure member blocking said outlet opening, theinflation gas comprising a combustible mixture of gases including a fuelgas, an inert gas, and an oxidizer gas for supporting combustion of thefuel gas; igniting the mixture of gases inside the combustion chamber toprovide heat of combustion created by burning of the fuel gas, themixture of gases, when ignited, inflating the vehicle occupantrestraint; forming warm inflation gas by heating the inflation gas inthe container structure with the heat of combustion; rupturing theclosure member; and directing the warm inflation gas from the containerstructure toward the vehicle occupant restraint to inflate therestraint.
 67. A method as defined in claim 66 wherein said step ofstoring said inflation gas comprises the step of storing said fuel gasand said oxidizer gas separately from each other, said step of formingsaid warm inflation gas comprising the step of mixing said fuel gas andsaid oxidizer gas to form a combustible mixture of gases upon theoccurrence of a vehicle collision.
 68. A method as defined in claim 66wherein said inflation gas further comprises an inert gas, said step offorming said warm inflation gas including heating said inert gas.
 69. Amethod as defined in claim 68 wherein said fuel gas and said inert gasare stored separately from each other.
 70. A method as defined in claim68 wherein said oxidizer gas and said inert gas are stored separatelyfrom each other.
 71. A method as defined in claim 68 wherein said fuelgas, said oxidizer gas and said inert gas are stored separately fromeach other.
 72. A method as defined in claim 66 wherein said step ofigniting said fuel gas comprises the step of transmitting energy from anenergy source to said fuel gas through an imperforate wall portion ofsaid container structure.
 73. A method as defined in claim 66 whereinsaid step of igniting said fuel gas comprises the step of spewingincandescent materials into said fuel gas from an elongate combustiblemeans for generating said incandescent materials.
 74. An apparatus forinflating a vehicle occupant restraint, said apparatus comprising: acontainer structure; a mixture of gases stored in said containerstructure, said stored mixture of gases comprising a combustible mixtureof ignitable fuel gas, an inert gas and an oxidizer gas; means forigniting said fuel gas, said fuel gas, when ignited, heating saidcombustible mixture of gases; and directing means for directing gasesfrom said container structure toward the vehicle occupant restraint toinflate the restraint.
 75. An apparatus as defined in claim 74 whereinsaid directing means directs occupant restraint inflating gas from saidcontainer structure to the vehicle occupant restraint to inflate therestraint, said occupant restraint inflating gas consisting of saidignited combustible mixture.
 76. An apparatus as defined in claim 74wherein said stored mixture of gases consists of said combustiblemixture.
 77. An apparatus as defined in claim 74 wherein said fuel gascomprises about 10-14 molar percent of said combustible mixture, saidoxidizer gas comprises about 15 to 25 molar percent of said combustiblemixture, and said inert gas comprises about 61-75 molar percent of saidcombustible mixture.
 78. An apparatus as defined in claim 74 whereinsaid combustible mixture comprises a fuel lean mixture of said fuel gasand said oxidizer gas.
 79. An apparatus as defined in claim 74 whereinsaid fuel gas is selected from the group consisting of hydrogen andgaseous hydrocarbons.
 80. An apparatus as defined in claim 74 whereinsaid igniter means includes an elongate heat source which extends fromone end portion of said container structure through a central portion ofsaid container structure.
 81. An apparatus as defined in claim 80wherein said container structure has a longitudinal central axis, saidelongate heat source being disposed on said longitudinal central axis.82. An apparatus as defined in claim 74 wherein said igniter meansincludes an elongate core disposed in a frangible sheath in saidcontainer structure, and further includes means for initiating burningof said core with a resultant shattering of said sheath and spewing ofincandescent reaction products into said combustible mixture along thelength of said elongate core.
 83. An apparatus as defined in claim 74wherein said container structure has an imperforate wall portion, saidigniter means including a source of energy disposed adjacent to a firstside of said imperforate wall portion, said igniter means furtherincluding actuatable means disposed adjacent to a second side of saidimperforate wall portion and actuatable due to energy transmittedthrough said imperforate wall portion to effect ignition of saidcombustible mixture.
 84. An apparatus as defined in claim 83 whereinsaid source of energy comprises a first ignitable charge adjacent tosaid first side of said imperforate wall portion, said actuatable meanscomprising a second ignitable charge disposed adjacent to said secondside of said imperforate wall portion.
 85. An apparatus for inflating avehicle occupant restraint, said apparatus comprising: a first chamber;a fuel gas stored in said first chamber; a second chamber separated fromsaid first chamber; an oxidizer gas stored in said second chamber, saidfuel gas and said oxidizer gas being released for flow into a containingmeans; and means for causing said stored fuel gas to mix with saidoxidizer gas and to ignite producing products of combustion, the mixtureof gases in the containing means being ignited, the mixture of gasesbeing directed into the vehicle occupant restraint to inflate thevehicle occupant restraint.
 86. An apparatus as defined in claim 85wherein said first and second chambers are respectively defined by firstand second containers which are separated from each other.
 87. Anapparatus as defined in claim 85 wherein said stored fuel comprises afuel gas.
 88. An apparatus as defined in claim 87 further comprisingcontaining means for receiving said fuel gas and said stored oxidizergas from said first and second chambers to provide a combustible mixtureof gases in said containing means, and an igniter for igniting saidcombustible mixture of gases in said containing means to produce saidproducts of combustion.
 89. An apparatus as defined in claim 88 whereinsaid containing means stores an inert gas.
 90. An apparatus forinflating a vehicle occupant restraint, said apparatus comprising: acontainer structure; a combustible mixture of gases in said containerstructure, said mixture of gases including a fuel gas, an inert gas, andan oxidizer gas for supporting combustion of said fuel gas, said fuelgas being selected from the group consisting of hydrogen and gaseoushydrocarbons; means for igniting said mixture of gases to heat saidgases to form occupant restraint inflating gas, said occupant restraintinflating gas comprising the ignited combustible mixture of gases, saidfuel gas, when ignited, heating said combustible mixture of gases; anddirecting means for directing said occupant restraint inflating gastoward the vehicle occupant restraint to inflate said vehicle occupantrestraint.
 91. An apparatus for inflating an inflatable vehicle occupantrestraint, said apparatus comprising: a container storing inflation gasfor inflating the restraint, said stored inflation gas consisting of acombustible mixture of gases comprising a fuel gas, an inert gas, and anoxidizer gas; igniter means for igniting said combustible mixture ofgases upon the occurrence of a vehicle collision, said fuel gas, whenignited, heating said mixture of gases; and directing means fordirecting said inflation gas from said container toward the restraint toinflate the restraint.
 92. An apparatus for inflating a vehicle occupantrestraint, said apparatus comprising: a container; a combustible mixtureof gases in said container, said mixture of gases comprising about 10 to14 molar percent of fuel gas, about 15 to 25 molar percent of anoxidizer gas and about 61-75 molar percent of an inert gas; means forigniting said fuel gas, said fuel gas, when ignited, heating saidmixture of gases to form occupant restraint inflating gas; and directingmeans for directing said occupant restraint inflating gas from saidcontainer toward the vehicle occupant restraint to inflate said vehicleoccupant restraint.
 93. An apparatus for inflating a vehicle occupantrestraint, said apparatus comprising: a container; a combustible mixtureof gases in said container, said combustible mixture of gases comprisinga fuel lean mixture of a fuel gas, an inert gas, and an oxidizer gas;means for igniting said fuel gas, said fuel gas, when ignited, heatingsaid mixture of gases to form occupant restraint inflating gas; anddirecting means for directing said occupant restraint inflating gas fromsaid container toward the vehicle occupant restraint to inflate saidvehicle occupant restraint, said combustible mixture of gases being fuellean such that said occupant restraint inflating gas is substantiallyfree of fuel gas and includes remaining oxidizer gas.
 94. An apparatusfor inflating a vehicle occupant restraint, said apparatus comprising: acontainer containing a combustible mixture of gases including a fuelgas, an inert gas and an oxidizer gas, said oxidizer gas being about15-25 molar percent of said combustible mixture of gases; igniter meansfor igniting said fuel gas in said container, said fuel gas, whenignited, heating said mixture of gases in said container; and directingmeans for directing said gases from said container to the vehicleoccupant restraint to inflate the vehicle occupant restraint.
 95. Anapparatus as defined in claim 94 wherein said fuel gas is about 10-14molar percent of said combustible mixture of gases.
 96. A method ofinflating a vehicle occupant restraint, said method comprising the stepsof: providing a combustible mixture of gases in a container, thecombustible mixture of gases including a fuel gas, an inert gas and anoxidizer gas, the oxidizer gas being about 15-25 molar percent of thecombustible mixture of gases; igniting the mixture of gases in thecontainer to heat the mixture of gases in the container, the mixture ofgases, when ignited, inflating the vehicle occupant restraint; anddirecting the heating gases from the container to the vehicle occupantrestraint to inflate the vehicle occupant restraint.
 97. A method asdefined in claim 96 wherein said fuel gas is about 10-14 molar percentof said combustible mixture of gases.
 98. A method of inflating avehicle occupant restraint, said method comprising the steps of:providing a combustible mixture of gases in a container, the combustiblemixture of gases including a fuel gas, an inert gas, and an oxidizergas, the oxidizer gas being about 15-25 molar percent of the combustiblemixture of gases; providing a means separate from and independent of thecombustible mixture of gases for opening the container; opening thecontainer by the means separate from and independent of the combustiblemixture of gases; igniting the combustible mixture of gases to heat themixture of gases in the container, the mixture of gases, when ignited,inflating the vehicle occupant restraint; and directing the mixture ofgases from the container to the vehicle occupant restraint to inflatethe vehicle occupant restraint.
 99. A method as defined in claim 98wherein said fuel gas is about 10-14 molar percent of said combustiblemixture of gases.